I used this software for partitioning purposes from 2003 to 2008 on a Win XP Pro system having since moved over to Easeus Partition Manager Pro.
If your still using PM8 (which is not compatible with Win Vista or Win 7) I strongly recommend that you apply the EMPM801-H1 patch - if you can find it online that is - which upgrades the product build to 1312 and resolves Error 1513 "Bad attribute position in file record."
PM8 is quick to install and easy to use and any changes that you make (resizing, merging, deletes) can be viewed in preview mode before actually applying them for real and undone if necessary without issue. Depending on the changes made they will either be completed within Windows or require a reboot and be completed before Windows restarts which typically occurs when making changes that effect the OS partition.
Partitioning can take some time in situations where you have a lot of existing data to be moved and its important to allow PM8 time to complete even if not much appears to be happening! Canceling a partitioning operation once started can result in data loss or corruption.
Also while I have used PM8 any number of times without issue a power-loss during partitioning would also likely lead to data loss and/or corruption. It is for this reason that its important to back up your data before using it since this could save some heartache down the line! If you have access to a UPS (uninterruptible power supply) more the better.
In summary then PM8 remains good software but there are now a number of good paid and free alternatives to it now and if you've moved beyond XP you'll have no choice but to use them. Its relative ease of use belies the fact that this is powerful software with a lot going on 'under the hood'. It must therefore be used with care and only after backing up your data.
Symantec Norton Partition Magic is well known for hardisk management. I have been using it for a very long time (at least 6 years). It is very useful to install multiple operating systems, resize partitions freely without worrying data loss, merge or split partitions, hide or unhide partitions, and format converter (between FAT and NTFS). Without it, such tasks are very time-consuming. The tool so called bootmagic can manage the boot sequence. If we have a few OSs, we can choose which one we want to boot from.
The installation is simple and not slow. To complete every task, if we are not sure, we can check the HELP, flash tutorials, a PDF user guide or official website support. In a quick time, we can learn how to use it. The interface is user-friendly. After using long time, it nevers hurt me.
The drawback is that the software does not support Windows Vista OS.
*this review is also on ciao*